Electric heating device



Jan. 3, 1928. l 654 842 L. A. SMITH ET AL ELECTRIC HEATING DEVICE 2 sheets-sheet 1 Filed May 14, 1927 Arf!! BY/j n ATTORNEY ya l Jan. 3, 1928.

1,654,842 L. A. SMITH ET AL ELECTRIC HEATING DEVICE Filed May 14, 1927 2 sheets-sheet 2 l M umm IHM 4f f5 A TTORNEY rammed Jaa. s, 192e.

Unirse stares LEON A. SMTH AND RUDOLF BZEMINIECKI, F WASHINGTON,

TlISTRCT OF COLUMBIA.

unsern-Io Huertas naviera.

Appiicaiioa fried may i4,

This invention relates to electric heating devices and has special reference to an iinproved electric heating device for use in boilers, bath tubs, .steam generating appa-l iatus such as locomotive. and other steam boilers. and i'or use in heating water in pans, buckets and other receptacles as well as for use as a heating unit in stoves and the likeu One important object of the invention is 1C* to improve the general construction of devices of this character.

A second important object of the invention is to provide an improved device of this character in which special provision will l5 be made for maintaining the resistance element out ot contact with all metal parts so as to prevent short-circuiting, electric shocks and othei` injurious results.

A third important .object of the invention 2@ is to'provide an improved device ot this character so constructed that no Water or other liquid in which the device is emerged can. reach the resistance element used in heatingD f "With the above and other objects in'view as will be hereinafter apparent, the invention consists in general of certain novel details ot construction and combinations oi parts hereinafter fully described, illustrated in the accompanying drawings vand specically claimed. f

1n the accompanying drawings vlike charactors ot' reference indicate' like parts in the several views, and:

boiler showing the manner of applying the p invention thereto, provision being made whereby a number ot the heating elements .may be uscd'at diiierent points and the cenio trai portion ot the boiler being broken away to show the remainder` to a larger scale.

Figure 2 is a section through a portion oi the boiler shell showing how the invention is applied thereto.

' Figure 3 is a longitudinal median section taken througlitho device and showing a slightly modied form adapted for direct immersion in liquids as in bath tubs, dish pans and the like'.

liigure /l Ais an enlarged detail section on the line 4-4 ot Figure 3.

Figure 5 shows a modification ot the invention adapted 'tor use in stove body, this -modification beine' also suitable for use in dish pans and other like places.

, ed at its periphery for Figure 1 is a view of arwater heatingishell QQ. having a reduced vided at spaced points around 1927. Serial No. 191,357.

Figure 6 is a dianietric section through the modification illust-rated in Figure 5.

Figure 7 is a section on the line 7-7 ot Figure 6.

ln the forms of the invention shown in Figures 1 to 4 there is provided an outer shell 10 ot thin metal and ot tubular form, the shell being rounded and closed at one end as at 11 and provided at its remaining end with a thickened portion 19,. The shell at this end is open and the month is'interiorly threaded so that a plug 13 ot insulating material may be screwed into this threaded mouth, the flange 14 of this plug fitting tightly against the lower end ot' the shell. Extending centrally of the shell from the plug 13 and preferably' formed integrall therewith is a tubular support 15 Jfor the resistance clement. Around this support is spirally wound the coiled resistance element 16 and the wire of this element at one end passes through a suitable opening in the support 15 and down through the center of the support as shown at 17', emerging near the base sov that it may be engaged by the inner end ot a binding bolt or screw 18. The other end vot the resistance element is like-.- wisesecui'ed on the inner face ot the plug 13 beneath a second binding bolt or screw 19 and to the outer ends of the binding bolts are secured the respective line wires 20 having the usual insulating covering E21. Screwed onto the flange 14, which is thread-v this purpose, is a neck 23 and provided with a packing box 24 wherein is carried packing Q5 compressed by a packing gland QG onto the insulation 21 so that no water can enter the chamber formed Within the shell Q2 and consequently no water can enter the space Within the tube 10.

ln order to hold the support lcentrally of the tube 10 andv prevent any possibility of the resistance element 16 coming in` contact with the wall of said tube there is pro the tube one or more sets of segmento'fspherical recesses 27 whoi-ein are seated balls 28 preferably foi-ined ot' compressed isinglass or inica and contacting with the inner surface of the tube 10. Thus these balls prevent oscillation of the support 15 and the resistance element 16 cannot come in contact with the tube. Moreover, the balls permit easy withdrawal or replacement of the heating element, as for instance in case the element burns out as sometimes happens, the balls rolling on the inner Wall of the tube 10 to permit rotation of the plug 13 in unscrewing and. also to perinit longitudinal movement of the support and heating element.

In the form shown in Figure 3 the exterior of the thickened portion l2 is smooth, this Jterm being adapted for loose immersion in fluid such as in a bath tub or the like. ln the form shown in Figure 2 this thickened portion is screw threaded, this `form being used for insertion in a heating boiler, a steam boiler such as a stationary or locomo tive boiler or any like place Where the heating of the iiuid is preferably dene in a closed vessel. In order to enable the device to be inserted in the boiler Without leakage a construction such as shown in Figure 2 may be used wherein the boiler` shell is indicated at 29 and litted in this shell is a sleeve 30 having a flange 3l, the sleeve being internally threaded for engagement by the threadedi thickened portion 12. The flange Blrests inside ot the boiler shell 29 and iitting over the sleeve and resting against the outer suri'ace a packing Washer 32 of lead or other plastic material Which is forced tightlg7 against the shell 29 by a nut pAlso, on the thickened portion 12 is ornied a nut 34; by means ot which the device may be screwed into thesleeve 30.

ln the 'forni shown in Figures 5 to 7 in place ot the tubular arrangement there is provided a hollow disk like box or casing 35 wherein is located an annular support 36 for a resistance element 37 connected to a cable 35 through a neck 89 of the saine construction as the lower or neck portion of the forni shon'n in Figure. Balls 4l() of like material to the balls 28 are held in suitable depressions in the top, bottom and peripheral ifaces of the support 36 and serve to keep the element 37 i'roni contacting with the shell 35.

This forni of the device may, if desired, have short legs 41 which serve to support the device above the bottom of the dish pan or the like or Within a stove casing ft2 provided with a door 43 through which the device inay be inserted, the casing being mounted on legs 4.4.

ltis to be observed that the sizes and proportions of this device will vary in accordance with the service required and also that the materials ot' which it is made will be those found best adapted for this service. lt is also to be noted that a stop pin 4 5 may be employed at the upper end ot the tube ,l0 as shown in'Figure i llt Will also be noted that by properly proportioningr the threads on the part l2 the device may be used as a stopper for het Water bottles so that it may be placed in meeste such a bottle filled with cold Water and the bottle heated and kept hot. ln suche case, ho'svevr, it is preferred that the bottle be equipped with a. Wire guard to prevent the heating device troni coming in Contact With the sides of the bottle and injuring the latter or perhaps burning the person using the hot Water bottle.

There has thus been provided a simple and eilicient device of the kind described and 'tor the purpose specified.

lt is obvious that minor changes may be z nade in the torni and construction et the invention without departing from the mate'- rial spirit thereoi. it is not, therefore, desired to confine the invention to the enact torni herein shown and described, but it is desired to include all such as properly come Within the scope claimed.

Having thus described the invention, what is claimed as new, is:

l. ln a device of the kind described, a tubular shell closed at one end and open at the other, a plug of' insulating material screwed into said open end, a heating element support extending from the plug cent-rally of the shell and having ball receiving recesses formed therein, balls seated in said recesses and engaging the shell, a peripheral flange on said plug resting against the shell around the opening, binding posts extending through the plug into the shell, a` heating element carried b v said support and having its ends connected to theinner ends o' said posts, the outer ends of said posts forming means for attaching the Wires of a feed cable, and a second shell screwed en the tlange and having a packing bonr through which a cable may pass.

2. ln a device et the kind described, a tubular shell closed at one end and open at the other, a plug or' insulating material screwed into said open end, a heating element support extending l'roin the plug centrally of the shell and having ball receiving recesses formed therein, balls seated in said recesses and engaging the shell, a peripheral ilange on said plug resting against the shell around the opening, binding posts extending through the plug into the shell, a hea ting element carried bv said support and having its ends connected to the inner ends of said posts, the outer ends ot said posts 'forming ineans for attaching the wires oi a feed` cable, and a second shell screwed on the flange and having a packing box through which a cable may pass, the open end of Athe shell being thickened and externally threaded for screwinginto a. boiler.

ln testimony whereot'ivc ail'ix our signatures.

LEON A.' SliiiTll'. RUDLF lZlFlli/HNECK. 

